CD4 and systemic lupus erythematosus: Huang et al. reported that a subpopulation of CD4+CXCR5hiPD-1hiBCL-6+ circulating Tfh cells, rather than a population of CD4+CXCR5hiPD-1hi cells, was positively correlated with SLEDAI and anti-dsDNA antibody levels in the cTfh subpopulation of SLE patients.